Burglars Foil Alarm Systems
Their scheme: Cut a closed store’s phone lines. Hang back while cops respond to the alarm. After officers fail to spot anything wrong and drive away, break into the store and spend as much time as they need to make off with a weekend’s worth of cash.
And one I wrote about in Beyond Fear (page 56):
Attackers commonly force active failures specifically to cause a larger system to fail. Burglars cut an alarm wire at a warehouse and then retreat a safe distance. The police arrive and find nothing, decide that it’s an active failure, and tell the warehouse owner to deal with it in the morning. Then, after the police leave, the burglars reappear and steal everything.